Last Tuesday, people on the Amalfi coast in Italy saw more than one waterspout form offshore, fuelled by high humidity and relatively warm sea surface temperatures.
A waterspout is a column of rapidly rotating air, filled with cloud, which forms from a cumulus cloud above a large body of water. They are similar in appearance to small tornadoes but are typically far less powerful. A typical waterspout is about 50 metres wide with wind speeds of about 50mph, and lasts for only five to 10 minutes.
Given the warm, humid conditions necessary for them to develop, waterspouts are more commonly seen closer to the tropics, and are fairly rare in Italy at this time of year. Those along the Amalfi coast formed amid unsettled conditions associated with developing thunderstorms. One formed close to Salerno, and moved towards the city’s port at a relatively high speed but dissipated before causing any damage.
More impressively, another waterspout that formed near the town of Ravello drifted towards land, eventually crashing into a cliffside. There were no buildings in the vicinity and again no damage was reported.
Into the weekend, an area of low pressure deepened across the Adriatic Sea, earning the name Storm Bettina. The weather system brought unsettled conditions to southern and eastern parts of Europe through the weekend, spreading blustery winds and spells of showery rain across southern parts of Italy and Croatia from Friday night through much of Saturday.
Bettina then travelled north-east, across the Balkans and into the Black Sea by Sunday morning. During this time, much colder air was dragged in from the north, turning rain to snow across the Balkans. Razgrad in the north-east of Bulgaria recorded snow depths of 36cm by midday on Sunday, 28cm of which had fallen within 12 hours since the previous evening.
Tulcea and Brăila in south-east Romania had significant snowfall too with 12-14cm deposited within three hours on Sunday morning. Strong westerly-north-westerly winds were recorded, whipping up blizzards across the Odesa oblast in southern Ukraine that morning too.
Bettina began propagating northwards on Sunday night, with the centre of the low crossing western parts of Russia this morning – bringing snowfall, although relatively less intense.
